Table 2.

Biomimetic 3-D in vitro bone marrow and cancer models.

3-D Scaffold	Materials	Methods
Solid Scaffold	PLGA, PCL, PGDA, PVA and other polymers, fats, minerals, and microelements.	Solvent casting and porogen leaching, gas foaming, freeze-drying, electrospinning, and 3-D scaffold printing.
Hydrogel	Hyaluronic acid, Chitosan, Alginate, Collagen, Gelatin, Agarose, and others	Gel casting and use of molecular cross-linkers.
Matrigel	Basement membrane extract.	Gel casting.
Biocomposite scaffold	polymers, cells, growth factors.	Bioprinting using ink-jet, laser, valve, and acoustic based.
Scaffold-free systems	No scaffold material required. Delivery of cells and active biomolecules.	Magnetic levitation and self-assembly hanging drop method for spheroid formation.